期刊文献+
共找到64,323篇文章
< 1 2 250 >
每页显示 20 50 100
Oxidation Kinetics of Aluminum Powders in a Gas Fluidized Bed Reactor in the Potential Application of Surge Arresting Materials
1
作者 Hong Shih 《Materials Sciences and Applications》 2019年第3期253-292,共40页
In this technical paper, the oxidation mechanism and kinetics of aluminum powders are discussed in great details. The potential applications of spherical aluminum powders after oxidation to be part of the surging arre... In this technical paper, the oxidation mechanism and kinetics of aluminum powders are discussed in great details. The potential applications of spherical aluminum powders after oxidation to be part of the surging arresting materials are discussed. Theoretical calculations of oxidation of spherical aluminum powders in a typical gas fluidization bed are demonstrated. Computer software written by the author is used to carry out the basic calculations of important parameters of a gas fluidization bed at different temperatures. A mathematical model of the dynamic system in a gas fluidization bed is developed and the analytical solution is obtained. The mathematical model can be used to estimate aluminum oxide thickness at a defined temperature. The mathematical model created in this study is evaluated and confirmed consistently with the experimental results on a gas fluidization bed. Detail technical discussion of the oxidation mechanism of aluminum is carried out. The mathematical deviations of the mathematical modeling have demonstrated in great details. This mathematical model developed in this study and validated with experimental results can bring a great value for the quantitative analysis of a gas fluidization bed in general from a theoretical point of view. It can be applied for the oxidation not only for aluminum spherical powders, but also for other spherical metal powders. The mathematical model developed can further enhance the applications of gas fluidization technology. In addition to the development of mathematical modeling of a gas fluidization bed reactor, the formation of oxide film through diffusion on both planar and spherical aluminum surfaces is analyzed through a thorough mathematical deviation using diffusion theory and Laplace transformation. The dominant defects and their impact to oxidation of aluminum are also discussed in detail. The well-controlled oxidation film on spherical metal powders such as aluminum and other metal spherical powders can potentially become an important part of switch devices of surge arresting materials, in general. 展开更多
关键词 Aluminum Spherical Power GAS FLUIDIZATION Bed Oxidation Mechanism Oxide Growth Rate Gibbs Free Energy Ellingham Diagram Mathematical Modeling Dynamic System Plasma DIFFUSION DIFFUSION Coefficient Crystallographic defect Vacancy Pressure Temperature Flow Laplace Transform Equation Boundary Condition Ficks Second Law Software Experimental Theoretical SURGE ARRESTING MATERIALS Analytical Solution
下载PDF
Spatiotemporal expression of leukemia inhibitory factor receptor protein during neural tube development in embryos with neural tube defects
2
作者 Dong An Xiao-Wei Wei +3 位作者 He-Nan Zhang Dan Liu Wei Ma Zheng-Wei Yuan 《Neural Regeneration Research》 SCIE CAS CSCD 2020年第4期705-711,共7页
Leukemia inhibitory factor receptor(LIFR),as a neuroregulatory cytokine receptor,generally shows a neuroprotective effect in central nervous system injuries.In this study,to understand the effect of LIFR on pathogenes... Leukemia inhibitory factor receptor(LIFR),as a neuroregulatory cytokine receptor,generally shows a neuroprotective effect in central nervous system injuries.In this study,to understand the effect of LIFR on pathogenesis of neural tube defects,we explored spatiotemporal expression of LIFR at different stages of fetal development in normal and neural tube defect embryos.Spina bifida aperta was induced with all-trans retinoic acid on embryonic day 10 in rats,and the spatiotemporal expression of LIFR was investigated in spina bifida aperta rats and healthy rats from embryonic day 11 to 17.Real time-polymerase chain reaction and western blot assay were used to examine mRNA and protein expression of LIFR in healthy control and neural tube defect embryos.Results of the animal experiment demonstrated that expression of LIFR protein and mRNA in the spinal cords of normal rat embryos increased with embryonic development.LIFR was significantly downregulated in the spinal cords of spina bifida aperta rats compared with healthy rats from embryonic days 11 to 17.Immunohistochemical staining showed that the expression of LIFR in placenta and spinal cord in spina bifida aperta rat embryos was decreased compared with that in control embryos at embryonic day 15.Results from human embryo specimens showed that LIFR mRNA expression was significantly down-regulated in spinal cords of human fetuses with neural tube defects compared with normal controls at a gestational age of 24 to 33 weeks.The results were consistent with the down-regulation of LIFR in the animal experiments.Our study revealed spatiotemporal changes in expression of LIFR during embryonic neurulation.Thus,LIFR might play a specific role in neural tube development.All animal and human experimental procedures were approved by the Medical Ethics Committee of Shengjing Hospital of China Medical University,China(approval No.2016PS106K)on February 25,2016. 展开更多
关键词 amniotic fluid DEVELOPMENT EMBRYOGENESIS LEUKEMIA INHIBITORY factor receptor nerve regeneration neural tube defect PLACENTA spatiotemporal expression spina bifida aperta spinal CORD serum
下载PDF
Nursing Care of Patients With Transcatheter Closure of Atrial Septal Defect via Femoral Vein
3
作者 Qing Li Yaping Bai 《Journal of Advances in Medicine Science》 2018年第1期6-8,共3页
Objective:To explore the operative nursing coordination method for the treatment of congenital atrial septal defect(ASD)by transcatheter closure of atrial septal defect via femoral vein.It provides useful experience f... Objective:To explore the operative nursing coordination method for the treatment of congenital atrial septal defect(ASD)by transcatheter closure of atrial septal defect via femoral vein.It provides useful experience for the treatment of congenital heart disease.Methods a total of 12 patients undergoing minimally invasive atrial septal defect closure via femoral vein from January 2017 to November 2017 in our department of cardiac surgery were selected as the subjects.All patients received transesophageal ultrasound guided ASD occlusion by femoral vein.The operation and nursing contents include preoperative care,the cooperation of the itinerant nurses,the coordination of the instrument nurses and the postoperative nursing.Results the operation of 12 patients in this group was successful.The diameter of the occluder was 17.1+4.5 mm during the operation.The time of tracheal intubation was 2.4+0.7 h,from the femoral vein to the sheath tube time was 38.7+9.4 min,the occupancy of ICU was 12.5+2.6 h after the operation.The average time of hospitalization was 4.5+1.8 D.There were 2 cases of shunt 1mm immediately after operation.After 24h reexamination,the shunt disappeared,the heart murmur disappeared in the rest of the patients.No residual shunt and other complications occurred. 展开更多
关键词 TRANSCATHETER closure of atrial SEPTAL defect VIA femoral vein Congenital heart ward SEPTAL defect Esophagus ultrasound EXTRACORPOREAL DEFIBRILLATION electrode Operation nursing coordination
下载PDF
Mass Increase with Strong and Gravitational Potentials, and Mass Defect with Electromagnetic Potential
4
作者 Hany Ali Hussein 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第3期1079-1094,共16页
The proposal is “mass increases due to strong and gravitational potentials, while it decreases due to Electromagnetic potential”. This proposal explains the big difference in mass between hadrons (protons, neutrons,... The proposal is “mass increases due to strong and gravitational potentials, while it decreases due to Electromagnetic potential”. This proposal explains the big difference in mass between hadrons (protons, neutrons, & mesons) and their components (quarks), mass difference between nucleus and its individual components (protons and neutrons), massless of gamma photons, abnormal masses of mesons and bosons, and the excess in galaxy masses (dark matter). Also, this proposal shows the exact relation between mass and energy: Strong Potential=−3.04mc2| Electric Potential |=−5.57×10−3mc2Gravitational Potential=−1.22×10−7mc2where m represents the excess in mass due to strong potential, or gravitational potential and represents the decrease in mass due to electromagnetic potential. Released energy here equals potential energy and doesn’t equal decrease in mass using the formula E = mc2. Released energy is transferred to heat, photons, kinetic energy… Finally, proposal will try to describe the relation between photon energy and mass of its components using the general equation of kinetic energy: Photon Energy=1/2mc2m is the sum of the individual masses of its components, while the total mass of photon is zero. 展开更多
关键词 Mass defect Dark Matter PHOTON Gamma Photon Strong Potential Gravitational Potential Electromagnetic Potential QUARKS Mesons BOSONS Deuterium Proton Neutron
下载PDF
Healing Mechanism and Osteogenic Capacity of Bovine Bone Mineral—Human Amniotic Mesenchymal Stem Celland Autogenous Bone Graft in Critical Size Mandibular Defect
5
作者 David B. Kamadjaja   +4 位作者 Purwati Fedik A. Rantam   Ferdiansyah D. Coen Pramono 《Journal of Biomedical Science and Engineering》 2015年第10期733-746,共14页
Experiments on maxillofacial bone tissue engineering showed the promising result;however, its healing mechanisms and effectiveness had not been fully understood. The aim of this study is to compare the bone healing me... Experiments on maxillofacial bone tissue engineering showed the promising result;however, its healing mechanisms and effectiveness had not been fully understood. The aim of this study is to compare the bone healing mechanism and osteogenic capacity between bovine bone mineral loaded with hAMSC and autogenous bone graft in the reconstruction of critical size mandibular bone defect. Critical size defects were made at the mandible of 45 New Zealand white rabbits reconstructed with BBM-hAMSC, BBM alone, and ABG, respectively. At the end of first, second, and twelfth weeks, five rabbits from each experimental week were sacrificed for histology and immunohistochemistry staining. Expressions of vascular endothelial growth factor (VEGF), bone mor-phogenic proteins-2 (BMP2), Runx2 and the amount of angiogenesis were analyzed in the first and second week groups, while expressions of Runx2, osteocalcin, collagen type-I fibres, trabecular area and bone incorporation were analyzed in the twelfth week groups. The result showed that expressions of VEGF, BMP2 and Runx2 as well as the amount of angiogenesis were higher in ABG compared with BBM-hAMSC group in the first and second weeks of healing. The result of twelfth week of healing showed that expressions of Runx2 and osteocalcin as well as the thickness of collagen type-I fibres were significantly higher in BBM-hAMSC compared to ABG group, while there was no statistically difference in trabecular area and bone incorporation between BBM-hAMSC and ABG group. This study concluded that early healing activities were higher in auto-genous bone graft than in BBM-hAMSC, while osteogenic activities in the late stage of healing were higher in BBM-hAMSC compared to autogenous bone graft. It was also concluded that the osteo-genic capacity of BBM-hAMSC was comparable to autogenous bone graft in the reconstruction of critical size defect in the mandible. 展开更多
关键词 BONE HEALING MECHANISM OSTEOGENIC Capacity Human Amniotic Mesenchymal Stem Cell Bovine BONE MINERAL AUTOGENOUS BONE Graft Critical Size Mandibular BONE defect
下载PDF
Hepatitis B virus infection:defective surface antigen expression and pathogenesis 被引量:11
6
作者 Chun-Chen Wu Ying-shan Chen +2 位作者 Liang Cao Xin-Wen Chen Meng-ji Lu 《World Journal of Gastroenterology》 SCIE CAS 2018年第31期3488-3499,共12页
Hepatitis B virus(HBV) infection is a global public health concern. HBV causes chronic infection in patients and can lead to liver cirrhosis, hepatocellular carcinoma, and other severe liver diseases. Thus, understand... Hepatitis B virus(HBV) infection is a global public health concern. HBV causes chronic infection in patients and can lead to liver cirrhosis, hepatocellular carcinoma, and other severe liver diseases. Thus, understanding HBV-related pathogenesis is of particular importance for prevention and clinical intervention. HBV surface antigens are indispensable for HBV virion formation and are useful viral markers for diagnosis and clinical assessment. During chronic HBV infection, HBV genomes may acquire and accumulate mutations and deletions, leading to the expression of defective HBV surface antigens. These defective HBV surface antigens have been found to play important roles in the progression of HBV-associated liver diseases. In this review, we focus our discussion on the nature of defective HBV surface antigen mutations and their contribution to the pathogenesis of fulminant hepatitis B. The relationship between defective surface antigens and occult HBV infection are also discussed. 展开更多
关键词 HEPATITIS B SURFACE protein defectIVE SURFACE antigen mutants Endoplasmic reticulum stress FULMINANT HEPATITIS B OCCULT HEPATITIS B virus infection PATHOGENESIS
下载PDF
Lethal Developmental Defects: An Overview
7
作者 Ashutosh Halder 《Open Journal of Obstetrics and Gynecology》 2014年第16期1006-1036,共31页
About 3% of all conceptions are associated with major congenital malformations, many of them are lethal developmental defect and genetic in origin or teratogenic (adverse effects of the environment during gametogenesi... About 3% of all conceptions are associated with major congenital malformations, many of them are lethal developmental defect and genetic in origin or teratogenic (adverse effects of the environment during gametogenesis or early embryogenesis). Genetics with or without adverse environment has role in virtually every developmental defect/malformation disorders in causation, predisposition, susceptibility & modulation of disease. Advances in genetics, introduction of triple marker screening, routine obstetric ultrasound examination into obstetric practice & accesses to prenatal diagnosis helped in secondary prevention (early detection & termination) of lethal developmental defects. Ultrasound detection of fetal developmental defects/malformation is common now and often decision on pregnancy solely based on ultrasonic morphological description. This practice leads to difficulty in providing accurate counseling as well as preventing disorder in subsequent pregnancy, in particular early. Hence an understanding of reproductive genetics of major developmental disorders is important for today’s perinatal care specialists. This overview will outline the various lethal developmental defects observed in an advanced reproductive genetics set up and various approaches adopted to derive diagnosis. Detailed assessment of fetus after termination of pregnancy (spontaneous/induced) for fetal anomalies was carried out in most cases. As most cases was referred after termination in formalin routine chromosomal analysis was not possible however, in selected cases targeted FISH analysis with specific chromosomal probe was carried out to confirm clinical diagnosis. Detailed evaluation of fetus is important as this practice often helped in modification of genetic counseling, as well as course of management in the next pregnancy. No molecular diagnostic or screening work was carried out due to non availability of information and facility in past. However, this is important today as many of the lethal developmental defects are yet to be categorized etiopathologically, and hence immediate need is to start clinical registry along with biorepository of developmental defects cases for future research work on informative families, in particular with multiple affected fetuses/sibs, using genomics, proteomics, metabolomics, platforms. 展开更多
关键词 LETHAL Developmental defect LETHAL MALFORMATION Neural Tube defect CHROMOSOMAL ABNORMALITY Amniotic Band Syndrome Skeletal Dysplasia Nonimmune HYDROPS Fetalis
下载PDF
A PAT STUDY OF INFLUENCES OF PRECIPITATION ON DEFECTS AND ELECTRONIC DENSITY IN Al-Li-Cu-Mg-Zr ALLOYS 被引量:2
8
作者 Wu, WM Gao, YJ +4 位作者 Luo, LX Deng, W Xu, SJ Zhong, XP Jiang, XJ 《中国有色金属学会会刊:英文版》 CSCD 1997年第1期43-46,共4页
APATSTUDYOFINFLUENCESOFPRECIPITATIONONDEFECTSANDELECTRONICDENSITYINAlLiCuMgZrALLOYS①WuWeiming,GaoYingjun... APATSTUDYOFINFLUENCESOFPRECIPITATIONONDEFECTSANDELECTRONICDENSITYINAlLiCuMgZrALLOYS①WuWeiming,GaoYingjun,LuoLixiong,DengW... 展开更多
关键词 positron lifetime spectra Al Li Cu Mg ZR alloy ageing PRECIPITATION defectS bulk ELECTRONIC DENSITY
下载PDF
Frontiers in research on maternal diabetes-induced neural tube defects:Past,present and future 被引量:2
9
作者 Shyamasundar Sukanya Boon Huat Bay +1 位作者 Samuel Sam Wah Tay S Thameem Dheen 《World Journal of Diabetes》 SCIE CAS 2012年第12期196-200,共5页
Diabetes mellitus rightly regarded as a silent-epidemic is continually on the rise and estimated to have a global prevalence of 6.4 % as of 2010.Diabetes during pregnancy is a well known risk factor for congenital ano... Diabetes mellitus rightly regarded as a silent-epidemic is continually on the rise and estimated to have a global prevalence of 6.4 % as of 2010.Diabetes during pregnancy is a well known risk factor for congenital anomalies in various organ systems that contribute to neonatal mortality,including cardiovascular,gastrointestinal,genitourinary and neurological systems,among which the neural tube defects are frequently reported.Over the last two to three decades,several groups around the world have focussed on identifying the molecular cues and cellular changes resulting in altered gene expression and the morphological defects and in diabetic pregnancy.In recent years,the focus has gradually shifted to looking at pre-programmed changes and activation of epigenetic mechanisms that cause altered gene expression.While several theories such as oxidative stress,hypoxia,and apoptosis triggered due to hyperglycemic conditions have been proposed and proven for being the cause for these defects,the exact mechanism or the link between how high glucose can alter gene expression/transcriptome and activate epigenetic mechanisms is largely unknown.Although preconceptual control of diabetes,(i.e.,managing glu-cose levels during pregnancy),and in utero therapies has been proposed as an effective solution for managing diabetes during pregnancy,the impact that a fluctuating glycemic index can have on foetal development has not been evaluated in detail.A tight glycemic control started before pregnancy has shown to reduce the incidence of congenital abnormalities in diabetic mothers.On the other hand,a tight glycemic control after organogenesis and embryogenesis have begun may prove insufficient to prevent or reverse the onset of congenital defects.The importance of determining the extent to which glycemic levels in diabetic mothers should be regulated is critical as foetal hypoglycemia has also been shown to be teratogenic.Finally,the major question remaining is if this whole issue is negligible and not worthy of investigation as the efficient management of diabetes during pregnancy is well in place in many countries. 展开更多
关键词 Maternal diabetes CONGENITAL anomalies NEURAL tube defects HYPERGLYCEMIA Hypoxia Oxidative stress NEURAL stem cells EPIGENETICS EPIGENOME
下载PDF
Role of Reversed Sural Artery Flap in Reconstruction of Lower Third of the Leg, Ankle and Foot Defects
10
作者 Mohamed Elsayed Mohamed Mohamed Belal A. Al Mobarak 《Modern Plastic Surgery》 2018年第3期50-59,共10页
Introduction: Coverage of defects of the distal lower extremity and foot remains a challenging reconstructive prcedure. Free tissue transfer remains the standard for the management of these defects. However, there are... Introduction: Coverage of defects of the distal lower extremity and foot remains a challenging reconstructive prcedure. Free tissue transfer remains the standard for the management of these defects. However, there are some disadvantages like;longer operative times, bulky contour, and the need for highly skilled expertise. The reverse superficial sural artery flap (RSSAF) is a distally based fasciocutaneous or adipo-fascial flap that is used for coverage of defects that involve the distal third of the leg, ankle, and foot. A significant advantage of this flap is a constant blood supply that does not require sacrifice of a major artery. Methods: Twenty RSSAF flaps were harvested for reconstruction of different traumatic soft tissue defects of the lower third of leg, ankle and foot. Follow up for 6 months postoperative. Results: Twenty Patients;twelve males and eight females underwent reconstruction of different soft tissue defects over the foot and ankle using RSSAF. The overall complications occurred in 6 flaps;4 minor and 2 major complications. The remaining 14 flaps passed an uneventful follow up. Conclusions: The reverse superficial sural artery flap RSSAF can be used as a reliable alternative to free tissue transfer in reconstruction of defects over the lower third of leg, ankle, and foot. Venous congestion is the major threat to the flap but its incidence can be minimized by wide pedicle, less kink of the flap, and keep the venae comitants around the artery. 展开更多
关键词 Role of Reversed SURAL ARTERY FLAP in Reconstruction of Lower Third of the LEG ANKLE and FOOT defects
下载PDF
Some recent advances in ab initio calculations of nonradiative decay rates of point defects in semiconductors 被引量:1
11
作者 Linwang Wang 《Journal of Semiconductors》 EI CAS CSCD 2019年第9期26-31,共6页
In this short review,we discuss a few recent advances in calculating the nonradiative decay rates for point defects in semiconductors.We briefly review the debates and connections of using different formalisms to calc... In this short review,we discuss a few recent advances in calculating the nonradiative decay rates for point defects in semiconductors.We briefly review the debates and connections of using different formalisms to calculate the multi-phonon processes.We connect Dr.Huang's formula with Marcus theory formula in the high temperature limit,and point out that Huang's formula provide an analytical expression for the phonon induced electron coupling constant in the Marcus theory formula.We also discussed the validity of 1D formula in dealing with the electron transition processes,and practical ways to correct the anharmonic effects. 展开更多
关键词 SCF SOME recent advances in ab INITIO calculations of nonradiative DECAY rates of point defects in SEMICONDUCTORS
下载PDF
Numerical prediction of thermo-hydrodynamics on the gas-lubricated film in wedge-shaped microchannel
12
作者 ZHANG Xueqing ZHANG Yangang +1 位作者 CHEN Qinghua LIU Juanfang 《排灌机械工程学报》 EI CSCD 北大核心 2019年第8期692-698,共7页
One wedge-shaped microchannel was established,and the hydrodynamic properties of the wedge-shaped gas film were comprehensively investigated.The Navier-Stokes equations coupled with the full energy equation were adopt... One wedge-shaped microchannel was established,and the hydrodynamic properties of the wedge-shaped gas film were comprehensively investigated.The Navier-Stokes equations coupled with the full energy equation were adopted to mainly analyze the lubrication hydrodynamics of the gas film,as the horizontal plate was viewed as the adiabatic wall or the horizontal plate temperature was equal to the tilt plate temperature.A higher gas film temperature strengthened the rarefaction effect,and the more rarefied gas weakened the squeeze.Meanwhile,the vertical flow across the gas film could indicate the relation between the velocity vector and the gas film squeeze and expansion.The adiabatic horizontal plate could resist the heat conduction and enhance the rarefaction effect,and thus the direction of motion of the gas molecules was easier to be changed. 展开更多
关键词 thermo-hyrodynamics Navier-Stokes equations adiabatic horizontal plate wedge-shaped gas-lubricated FILM
下载PDF
Defect Engineering:Can it Mitigate Strong Coulomb Effect of Mg^(2+)in Cathode Materials for Rechargeable Magnesium Batteries?
13
作者 Zhengqing Fan Ruimin Li +3 位作者 Xin Zhang Wanyu Zhao Zhenghui Pan Xiaowei Yang 《Nano-Micro Letters》 SCIE EI CAS 2025年第1期135-159,共25页
Rechargeable magnesium batteries(RMBs)have been considered a promising“post lithium-ion battery”system to meet the rapidly increasing demand of the emerging electric vehicle and grid energy storage market.However,th... Rechargeable magnesium batteries(RMBs)have been considered a promising“post lithium-ion battery”system to meet the rapidly increasing demand of the emerging electric vehicle and grid energy storage market.However,the sluggish diffusion kinetics of bivalent Mg^(2+)in the host material,related to the strong Coulomb effect between Mg^(2+)and host anion lattices,hinders their further development toward practical applications.Defect engineering,regarded as an effective strategy to break through the slow migration puzzle,has been validated in various cathode materials for RMBs.In this review,we first thoroughly understand the intrinsic mechanism of Mg^(2+)diffusion in cathode materials,from which the key factors affecting ion diffusion are further presented.Then,the positive effects of purposely introduced defects,including vacancy and doping,and the corresponding strategies for introducing various defects are discussed.The applications of defect engineering in cathode materials for RMBs with advanced electrochemical properties are also summarized.Finally,the existing challenges and future perspectives of defect engineering in cathode materials for the overall high-performance RMBs are described. 展开更多
关键词 Rechargeable magnesium battery Sluggish diffusion kinetic defect engineering Cathode materials Ion migration
下载PDF
带神经、血管预构皮瓣的动物实验及临床应用研究 被引量:2
14
作者 孙占胜 王伯珉 +4 位作者 王永会 张云峰 李连欣 穆卫东 陈振强 《山东医药》 CAS 北大核心 2005年第12期13-14,共2页
目的 探讨带神经、血管的预构皮瓣治疗四肢严重皮肤缺损的可行性。方法 动物实验:新西兰大耳白兔15只,随机分为3组各5只。A组:植入腹壁下动静脉血管束;B组:植入阴部外动静脉血管束;C组:植入股动静脉血管束及部分股神经。术后3周观察... 目的 探讨带神经、血管的预构皮瓣治疗四肢严重皮肤缺损的可行性。方法 动物实验:新西兰大耳白兔15只,随机分为3组各5只。A组:植入腹壁下动静脉血管束;B组:植入阴部外动静脉血管束;C组:植入股动静脉血管束及部分股神经。术后3周观察血管、神经生长情况。临床应用:手背皮肤缺损患者2例,用腹壁下深动脉和股外侧皮神经转移至腹壁皮下预构皮瓣,修复创面。结果 动物实验:3组预构皮瓣血管生长良好,C组可见少量神经纤维和轴突向远端生长。临床应用:2例患者皮瓣全部成活良好,且有皮肤浅感觉。结论 预制带神经、血管的皮瓣并用于治疗四肢严重皮肤缺损是可行的。 展开更多
关键词 西 C
下载PDF
计算机辅助设计下颌骨带种植体三维钛网的实验研究 被引量:12
15
作者 张庆福 吕春堂 +3 位作者 樊堂堂 周中华 汪大林 李郝林 《口腔颌面外科杂志》 CAS 2005年第2期156-158,共3页
目的:探讨利用计算机辅助方法,制作可用于下颌骨个体化功能性重建的修复体,为下颌骨个体化功能性修复探索新的方法。方法:首先通过CT扫描获取下颌骨断层解剖信息,然后运用三维重建、镜像及快速原型技术获得拟修复下颌骨复原实体模型,在... 目的:探讨利用计算机辅助方法,制作可用于下颌骨个体化功能性重建的修复体,为下颌骨个体化功能性修复探索新的方法。方法:首先通过CT扫描获取下颌骨断层解剖信息,然后运用三维重建、镜像及快速原型技术获得拟修复下颌骨复原实体模型,在此基础上利用铸造手段完成个体化三维钛网修复体的制作,然后将种植体与钛网相连接,构建个体化功能性修复体。结果:以CT扫描获取下颌骨断层解剖信息为基础,通过计算机辅助成功制作了带种植体的个体化钛网修复体,与相应的下颌骨标本连接匹配良好,个体化恢复了骨缺损的连续性,所带种植体为进行种植义齿修复恢复理想的咀嚼功能提供了可能。结论:在CT扫描获取下颌骨原始解剖信息的基础上,通过计算机CAD/CAM过程,能够成功构建下颌骨个体化功能性修复体,为临床个体化功能性颌骨重建提供了一种新的途径。 展开更多
关键词 CAD/CAM CT 齿
下载PDF
胶原蛋白膜作为金葡液载体修复骨缺损的实验研究 被引量:5
16
作者 冯文岭 郑旺 《中国修复重建外科杂志》 CAS CSCD 北大核心 2005年第5期350-353,共4页
目的 验证胶原蛋白膜吸附金葡液后修复骨缺损的优越性。 方法 选用成年新西兰大白兔2 4只,随机分为2组,每组12只。手术造成桡骨标准缺损后,分别植入胶原蛋白-金葡液复合体(实验组)和单纯等量金葡液(对照组) ,于术后2、4、6及8周时行... 目的 验证胶原蛋白膜吸附金葡液后修复骨缺损的优越性。 方法 选用成年新西兰大白兔2 4只,随机分为2组,每组12只。手术造成桡骨标准缺损后,分别植入胶原蛋白-金葡液复合体(实验组)和单纯等量金葡液(对照组) ,于术后2、4、6及8周时行大体、X线片、组织学及免疫组织化学观察。 结果 整个过程中实验组缺损区新生骨组织增殖明显、持续时间较长,且无过量结缔组织生长;X线片可见连续性骨痂通过缺损区,分布均匀;组织学观察可见多个成骨中心,骨小梁排列有序,成熟骨替代完全;免疫组织化学染色可见骨形成蛋白分布持续时间长,而且在新骨组织中占据范围大。对照组缺损区新生骨组织在质量和数量上都较实验组差。 结论 胶原蛋白能够阻挡周围软组织进入缺损区,为新骨生长提供空间;同时作为金葡液的载体,能减少金葡液外溢。 展开更多
关键词 西 X线
下载PDF
A Brief Analysis of the Differences and Defects of Subtitling Compared to Dubbing——Harry Potter and the Philosopher’s Stone
17
作者 官文莉 《神州》 2014年第12期133-133,共1页
Compared to the dubbing, the version of subtitling has many defects, including the faults purely in language translation and the inaccuracy in the cultural images. As a media of cultural communication, the translator ... Compared to the dubbing, the version of subtitling has many defects, including the faults purely in language translation and the inaccuracy in the cultural images. As a media of cultural communication, the translator of the subtitling has to pay enough attention to the art of language, and has to take strategies centering on the audience, promoting the cultural communication and reducing the cultural differences. 展开更多
关键词 A BRIEF Analysis of the Differences and defectS of SUBTITLING Compared to DubbingHarry POTTER and the Philosophers STONE
下载PDF
Intra-Atomic Gravitational Shielding (Lensing), Nuclear Forces and Radioactivity 被引量:3
18
作者 Robert A. Sizov 《Journal of Modern Physics》 2019年第1期59-73,共15页
The discovery by the author of real magnetic charges and true anti-electrons in the atomic structures allowed him to establish that the gravitational field (GF) in reality is the vortex electromagnetic field. Dependin... The discovery by the author of real magnetic charges and true anti-electrons in the atomic structures allowed him to establish that the gravitational field (GF) in reality is the vortex electromagnetic field. Depending on the vector conditions the gravitational fields can be either paragravitational (PGF) or ferrogravitational (FGF). Masses (atoms, nucleons, etc.) emitting PGF manifest so-called attraction to each other. In fact, this process is the pressing of atoms or nucleons to each other by the forces of gravitational “Dark energy”. Namely the gravitational “Dark energy” which is formed between the masses emitting PGF and compressing of nucleons in atomic nuclei is the main force factor determining the formation of nuclear forces. Masses that emit FGF are repelled from PGF sources, for example, from the Earth. The last gravitational manifestation, discovered by the author, this is of the effect of the gravitational levitation. The atomic shell and atomic nucleus are autonomous sources of gravitational field in atomic compositions. The gravitational fields emitted these sources, by its physical parameters, are different gravitational fields, what associated with differences in the magnitudes charges of magnetic and electric particles in their compositions. The noted differences in the parameters of the GF are of reason that in atoms the process of extrusion of foreign gravitational field from the region of given gravitational source is realized. This effect should be called the effect of intra-atomic gravitational shielding (IAGS). Within the framework of this effect the shell of the atom is a kind of gravitational “insulator” that prevents the PGF of the nucleons from leaving beyond of the atom. As result of the IAGS effect, the concentration PGF of nucleons is realized only in the region of the nucleus, which leads to an increase in nuclear forces. However, the resistance of the marked “insulator” is finite and if the critical voltage PGF on the nucleus is exceeded, the complete shielding of the nucleon fields by the atomic shell is broken. As result of the leakage of a part of the PGF of nucleons beyond the atom, the density of this field in the region of the nucleus decreases significantly, which leads to a weakening of the nuclear forces and often leads to radioactivity. The effect of gravitational shielding is directly related to such a well-known concept as the mass defect of the nucleus. It is the exclusion of the gravitational field formed by the nucleons in the composition of the atomic nucleus as a result of the full IAGS effect that creates the illusion of atomic mass defect. 展开更多
关键词 Magnetic CHARGES Antielectrons Magnetons Antimagnetons Bispinors Physical MASS Negative MASSES Vortex Electromagnetic (Gravitational) Field Paragravitation and Ferrogravitation Dark Energy GRAVITATIONAL SHIELDING (Lensing) defect of MASS Nuclear Forces
下载PDF
Droplet Self-Driven Characteristics on Wedge-Shaped Surface with Composite Gradients:A Molecular Dynamics Study
19
作者 Haowei Hu Xinnuo Chen +3 位作者 Qi Wang Qin Li Dong Niu Mu Du 《Frontiers in Heat and Mass Transfer》 EI 2024年第4期1071-1085,共15页
The self-driven behavior of droplets on a functionalized surface,coupled with wetting gradient and wedge patterns,is systematically investigated using molecular dynamics(MD)simulations.The effects of key factors,inclu... The self-driven behavior of droplets on a functionalized surface,coupled with wetting gradient and wedge patterns,is systematically investigated using molecular dynamics(MD)simulations.The effects of key factors,including wedge angle,wettability,and wetting gradient,on the droplet self-driving effect is revealed from the nanoscale.Results indicate that the maximum velocity of droplets on hydrophobic wedge-shaped surfaces increases with the wedge angle,accompanied by a rapid attenuation of driving force;however,the average velocity decreases with the increased wedge angle.Conversely,droplet movement on hydrophilic wedge-shaped surfaces follows the opposite trend,particularly in terms of average velocity compared to the hydrophobic case.Both wedge-shaped and composite gradient wedge-shaped surfaces are found to induce droplet motion,with droplets exhibiting higher speeds and distances on hydrophobic surfaces compared to hydrophilic surfaces,regardless of surface type.Importantly,the inclusion of wettability gradients significantly influences droplet motion,with hydrophobic composite gradient wedge-shaped surfaces showing considerable improvements in droplet speed and distance compared to their hydrophilic counterparts.By combining suitable wettability gradients with wedge-shaped surfaces,the limitations inherent in the wettability gradient range and wedge-shaped configuration can be mitigated,thereby enhancing droplet speed and distance.The findings presented in this paper offer valuable insights for the design of advanced functional surfaces tailored for manipulating droplets in real-world applications. 展开更多
关键词 Self-driven wettability gradient wedge-shaped surface composite gradient
下载PDF
Asymmetric and Single-Side Splitting of Dissipative Solitons in Complex Ginzburg–Landau Equations with an Asymmetric Wedge-Shaped Potential
20
作者 Yun-Cheng Liao Bin Liu +1 位作者 Juan Liu Jia Chen 《Chinese Physics Letters》 SCIE CAS CSCD 2019年第1期24-27,共4页
We report some novel dynamical phenomena of dissipative solitons supported by introducing an asymmetric wedge-shaped potential(just as a sharp ‘razor') into the complex Ginzburg–Landau equation with the cubicqui... We report some novel dynamical phenomena of dissipative solitons supported by introducing an asymmetric wedge-shaped potential(just as a sharp ‘razor') into the complex Ginzburg–Landau equation with the cubicquintic nonlinearity. The potentials corresponding to a local refractive index modulation with breaking symmetry can be realized in an active optical medium with respective expanding antiwaveguiding structures. Using the razor potential acting on a central dissipative soliton, possible outcomes of asymmetric and single-side splitting of dissipative solitons are achieved with setting different strengths and steepness of the potentials. The results can potentially be used to design a multi-route splitter for light beams. 展开更多
关键词 Dissipative Solitons COMPLEX GINZBURG-LANDAU Equations ASYMMETRIC wedge-shaped POTENTIAL
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部